MN - Starting The Year With A Bang - Franky Fox... |LINK|
Transplantation of allogeneic isolated islet cells allows one to avoideabdominal surgery. In 1983, human iL were transplanted to rats withexperimentally induced diabetes [60].The first allogenic iL transplantation into a Type I diabetic patient wasreported in 1990 [61]. However, theefficiency of this approach remained extremely poor until 2000. It is likelythat this was due to the limited techniques of islet isolation available at thetime, low islet yield, and severe immunosupression. Shapiro et al[62] developed the Edmontonprotocol that reduced the alloimmune response and improved the survival rate oftransplanted islets [62-64]. Owing to this protocol, the need forexogenous insulin was eliminated following islet transplantation. Moreover,Shamoon et al [65]reported that in patients receiving therapy glycosylated hemoglobin HbA1creached a normal level. The Edmonton protocol employs an enzymatic dissociationof islet cells. Islets are infused intraportally by portal veincatheterization, after which the cells become trapped in the venous sinuses ofthe recipient, have access to oxygen supply, and initiate glucose- dependentinsulin secretion. The important step in this procedure is a combination ofimmunosuppressive agents. Following infusion, the recipient receives daclizumabto prevent initial rejection. The use of another immunosuppressive component,sirolimus, allows one to avoid corticosteroid use, which shows toxicity toislet cells. The third agent, tacrolimus, is administered at small doses tominimize the side-effects it has on the islet mass. Current immunosuppressivetherapies are successful at reducing graft rejection rates and prolonging isletsurvival up to 5 years [66-68]. However, the risks of long-termimmunosuppression, as well as profound shortage of donor material, hinder thewidescale application of this procedure.
MN - Starting The Year With A Bang - Franky Fox...
Download File: https://www.google.com/url?q=https%3A%2F%2Furlcod.com%2F2ugrK5&sa=D&sntz=1&usg=AOvVaw2m3netTP69ZK5Dk8gvEaJC
Encapsulation materials may include water-soluble (alginate hydrogels) andwater-insoluble polymers [79]. Althoughalginates are water-soluble, they remain intact over several years [78, 80-84]. Creatingdoublelayered capsules contributes to decreased membrane porosity and enhancesmembrane durability and better immunoisolation. For protection against immunedestruction, membranes can be coated with poly-L-lysine and polyornithine inprejudice of mechanical stability and durability [79, 85, 86]. 041b061a72